With two GOP candidates expected to enter into a runoff, Nunn can continue campaigning and fundraising without an official opponent in a conservative-leaning state that her party hopes to claim.

But that doesn't mean the novice candidate -- who hope her last name still has some currency with voters -- will have it easy. In this race to replace retiring GOP Sen. Saxby Chambliss, Nunn is now facing real and tough questions about how she would legislate. Particularly regarding the Affordable Care Act, that will require a delicately crafted answer.

Unlike Democratic incumbents running in other Southern states such as Louisiana, Arkansas and North Carolina, Nunn doesn't have a vote to defend. But with the law's unpopularity in Georgia, she hasn't delivered a definitive answer yet either. To win in the Peach State, Nunn is counting on turnout from both the old and the new Democratic coalitions of whites, the young and African-Americans, respectively, as well as a sizable number of independents.

And, depending on Tuesday's results, Nunn could face a woman candidate in former Secretary of State Karen Handel, who hopes to neutralize a potential Democratic advantage among female voters.

"You can't put a 'war on women' on me," Handel told reporters at a regional airport here between campaign stops on Monday. "I'm the one conservative in this race -- who happens to be a she."

Nunn is more likely to align herself with George H.W. Bush than Barack Obama on the campaign trail. When asked about whether she would have voted for the health care law if she had been in Congress when it passed, Nunn noted that she was working at the time as the CEO of Points of Light Institute, a nonprofit volunteer organization inspired by the former Republican president's inaugural address.

In an interview with RealClearPolitics during a campaign stop at Francar's Buffalo Wings, Nunn said, "Looking back, I think we can all say we wished there had been more bipartisan support and engagement."

Last fall, Nunn backed a delay of the law's individual mandate to purchase insurance. And, in an ad last month, she opposed ACA subsidies for members of Congress. She proposes other fixes to the law, like adding another tier of insurance to alleviate high rates or extending tax credits for small businesses. But she says lawmakers need to "move forward" with coverage for pre-existing conditions and allowing adult children to remain on their parents' coverage plans till age 26.

"So there's a lot to work with," Nunn said. And, like other entrenched Democrats in similar states, she strongly approves the Medicaid expansion component of the ACA. While speaking with a group of supporters at the restaurant, Nunn said it was a mistake for Georgia to decline the federal money to expand Medicaid, and equated the decision by Republican Gov. Nathan Deal and the legislature to "sending taxpayer money to other states.''

(Republicans jumped on an MNSBC interview over the weekend in which Nunn said, as part of her answer to whether she would have voted for Obamacare, "It's impossible to look back retrospectively and say, 'What would you have done if you were there?'")

Nunn also voiced support for comprehensive immigration reform, saying she hopes to be a part of those discussions in Congress, and those for an increase in the federal minimum wage.

But beyond that, she has not aligned herself with fellow Democrats. Asked if President Obama would be a weight on her campaign, Nunn pointed to polls showing her ahead of the GOP candidates in head-to-head matchups. (The RCP Average finds Nunn narrowly leading four of her potential opponents but trailing one.) "I think ultimately Georgia voters know my name is on the top of this ballot, nobody else, and they are going to decide based on what they think is best for Georgia," she said.

For this candidate, the name means a great deal. Her father, Sam Nunn, served four terms in the Senate, including eight years as chairman of the Armed Services Committee. The elder Nunn is well respected in the state, and older voters the younger Nunn meets on the campaign will sometimes mention her father's first shoe-leather campaign in which he went from low name recognition to the nominee. He has appeared in an ad with his daughter, advises her on the trail, and his friend, Republican former Sen. Dick Lugar (who lost his Indiana seat in a primary last cycle), has steered money to the campaign.

In recalling her father "people harken back to a time, that wasn't so long ago but can actually seem quite distant, where we actually got things done, where we actually had people that worked across the aisle," Nunn said. "That legacy certainly puts me in good stead with voters and they're ready to hear that kind of message."

Whether they vote for it, though, remains to be seen. And it may not resonate with younger voters, as Sam Nunn hasn't been on the ballot since 1990.

"She's trading on her father's name and she's also trading on something I think is dishonest: She uses borrowed equity to make it seem like she's conservative because she worked for George Bush the elder," said David Bockel while getting his hair cut at Tommy's Barbershop in Atlanta, a popular stop for GOP politicians. Bockel is a Republican, but as the veterans program liaison for Georgia's Department of Economic Development, he attended an event Nunn held with veterans over the weekend.

"I think the world of Sam Nunn. Oh, my goodness, he is a true patriot. And I think Michelle is an excellent person," said Republican state Rep. Joe Wilkinson, who stopped in at the barbershop to support Rep. Jack Kingston's Senate bid. (Kingston, Handel and businessman David Perdue are the top three Republicans competing for a spot in the likely runoff.) "Frankly, [Democrats] are also going to be saddled with Barack Obama, who is very unpopular, and I personally believe a terrible disappointment." Given that, he said, Nunn stands to lose: "It's going to be 53-47, but that's not to say 10 years from now things are going to shift."

Democratic operatives in the state are hoping that a strong, if not successful, bid by Nunn will help them develop and advance the party organization and make the state more competitive for the presidential race of 2016. Obama lost Georgia twice, but by single digits, and the drop-off of white voters and increase in minorities, especially in and around Atlanta, has given Democrats hope of becoming a nationally competitive state. But even Democrats in the state acknowledge the challenge of getting there.

"It's challenging running as a Democrat in Georgia; there's no way around that. She's going to have to defy the odds to win here," said Bryan Long, executive director of Better Georgia, a progressive group working on building out an infrastructure in the state.

Long says the nine-week extended GOP primary (if no one wins more than 50 percent of Tuesday's vote) helps Nunn in that she can reach independent voters while her opponents appeal to conservatives for the nomination. But Nunn still has to run a near-flawless campaign, he said. Even as demographics in the state have moved in the party's favor, "Democrats have lost more elections," Long said. "Although demographics have been shifting, demographics don't win elections."

Nunn likely won't get an official opponent until late July, but Republicans running for the nomination often cite the Democrat's sizable war chest when making a pitch for their own electability.

"I think that Michelle Nunn is a formidable candidate and that's why, as we look at this field, to have the conservative candidate who can win is so important. And that individual is me," Handel told RCP. She listed her endorsements from Sarah Palin, Rick Santorum, and Georgia-based conservative blogger Erick Erickson. "They know I can beat her in the fall."

"I think [Democrats are] going to have a lot of money and they're going to invest and make a lot of noise," Kingston said. Can they win? "Only if we have the wrong nominee."